Clearwater Paper Corp — Proxy Solicitation & Information Statement 2026

Mar 27, 2026

DEFA14A 1 noticeandaccesscard.htm DEFA14A Document created using Wdesk Copyright 2026 Workiva Document

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

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SCHEDULE 14A Information

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934

(Amendment No. ___)

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Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

CHECK THE APPROPRIATE BOX:

☐	Preliminary Proxy Statement
☐	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
☐	Definitive Proxy Statement
☒	Definitive Additional Materials
☐	Soliciting Material Pursuant to §240.14a-12

CLEARWATER PAPER CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

PAYMENT OF FILING FEE (CHECK ALL BOXES THAT APPLY):

☒	No fee required.
☐	Fee paid previously with preliminary materials.
☐	Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11